Method and apparatus for forming cellular cores

ABSTRACT

A method and apparatus for forming cellular cores from sheet stock of paper, metal or plastic for use in the subsequent formation of laminated cellular panels, or for use independently to provide sound and thermal insulation. The process comprises the steps of feeding two or more webs of sheet material to be formed into the core; joining the webs by applying spaced lines of adhesive or the like between the webs along their direction of feed, bringing the webs into contact so as to cause them to join along said first applied lines of adhesive; applying spaced lines of adhesive or the like, spaced to lie between the previously applied adhesive lines on an outer face of the joined webs; simultaneously cutting a group-strip equal in length as measured along the web to the thickness of two or more layers of the final core product from the adhered webs transverse to their direction of movement; and packing and simultaneously cutting said groupstrip into two or more strips by moving them transverse to the direction of web feed to simultaneously form a plurality of layers of cellular cores of selected thickness. Apparatus suitable for performing the method is provided comprising supports for two or more supply rolls of web sheet material; means for feeding the sheet material from the supply rolls; sheet joining means such as adhesive applicators and laminating rolls arranged in the path of web feed for applying spaced lines of adhesive between the web surfaces; a final adhesive applicator for providing adhesive on the outer surface of one of said webs; pressure applying means for bringing two or more of the adhesive stripped web surfaces into contact to bond same along the first lines of adhesive application; cutting means for cutting groupstrips equal in length as measured in the direction of web feed to the thickness of two or more layers of the cellular core product from the advancing web transverse to the direction of movement; and packing-cutting means for simultaneously packing the group-strips against the strips of previously cut groupstrips and cutting the group-strips into a plurality of separate strips equal in length as measured along the web to the thickness of the cellular core product, said packing means packing two or more tiers of strips simultaneously.

United States Patent Hoyt 1 51 May 2,1972

[54] METHOD AND APPARATUSFOR FORMING CELLULAR CORES Edwin R. Hoyt, CoralGables, Fla. [73] Assignee: Core Cell Corporation, Bayamon, PR.

[22] Filed: June 2, 1969 [21] Appl. No; 829,167

[72] Inventor:

- FOREIGN PATENTS OR APPLICATIONS 909,444 10/1962 Great Britain 156/197Primary Eraminer-Benjamin A. Borchelt Assistant Examiner-G. E. MontoneA!10rne v-Robert W. Fiddler 5 7] ABSTRACT A method and apparatus forforming cellular cores from sheet stock of paper, metal or plastic foruse in the subsequent formation of laminated cellular panels, or for useindependently to provide sound and thermal insulation. The processcomprises the steps of feeding two or more webs of sheet material to beformed into the core; joining the webs by applying spaced lines ofadhesive or the like between the webs along their direction of feed,bringing the webs into contact so as to cause them to join along saidfirst applied lines of adhesive; applying spaced lines of adhesive orthe like, spaced to lie between the previously applied adhesive lines onan outer face of the joined webs; simultaneously cutting a group-stripequal in length as measured along the Web to the thickness of two ormore layers .of the final core product from the adhered webs transverseto their direction of movement; and packing and simultaneously cuttingsaid group-strip into two or more strips by moving them transverse tothe direction of web feed to simultaneously form a plurality of layersof cellular cores of selected thickness. Apparatus suitable forperforming the method is provided comprising supports for two or moresupply rolls of web sheet material; means for feeding the sheet materialfrom the supply rolls; sheet joining means such as adhesive applicatorsand laminating rolls arranged in the path of web feed for applyingspaced lines of adhesive between the web surfaces; a final adhesiveapplicator for providing adhesive on the outer surface of one of saidwebs; pressure applying means for bringing two or more of the adhesivestripped web surfaces into contact to bond same along the first lines ofadhesive application; cutting means for cutting group-strips equal inlength as measured in the direction of web feed to the thickness of twoor more layers of the cellular core product from the advancing webtransverse to the direction of movement; and packing-cutting means forsimultaneously packing the group-strips against the strips of previouslycut groupstrips and cutting the group-strips into a plurality ofseparate strips equal in length as measured along the web to thethickness of the cellular core product, said packing means packing twoor more tiers of strips simultaneously.

16 Claims, 4 Drawing Figures 70 69 6B 565 y @665; 1 76 I 77 0 2 67 h 69f -102- vl lea. 43 I 6 88 103 G625 H 9 j I l PATENTEDMAY 2 m2 3, 660. 195 INVENTOR EDWIN R4 HOYT mam ATTORNEY.

METHOD AND APPARATUS FOR FORMING CELLULAR CORES BACKGROUND OF THEINVENTION This invention relates to the art of cellular cores, and moreparticularly to an improved method and apparatus for forming cellularcores commonly referred to as honeycomb." The improved method andapparatus permits the simultaneous formation of a plurality of honeycomblayers of the same or different selected thicknesses.

Cellular cores have been widely used in forming a variety ofconstructional materials, to provide a lightweight relatively strongthermally, acoustically, and if desired electricallyinsulated'structure. These cellular cores are thus employed sandwichedbetween outer surface skins formed of sheet metal, or the like toprovide a relatively lightweight soundproof, and thermallyinsulated'member which may be used in forming walls, or the likebuilding components, for equipment housings, for pallets,'or for any ofa myriad of structural components. I

Such cellular cores may be fonned of sheet material of paper, sheetmetals, foils, sheet plastics or the like. Applicant in his prior patentU.S. Pat. No. 3,257,253 discloses apparatus for forming such cores ofpaper by training two or more webs of sheet paper stock to be formedinto the cellular cores to pass adjacent adhesive applicators so that aplurality of spaced adhesive lines are applied to one of the surfaces ofone of the webs, which surface is then brought into contact with asurface of another web to join the two webs together along the spacedlines of adhesive. Additionally. a plurality of spaced lines of adhesiveis applied to an outer surface of the joined webs intermediate the linesof application of the first lines of adhesive. Thereafter a strip of theadhesively joined webs is cut from the advancing joined webs and stackedwith a subsequently cut strip forced against a previously cut strip ofthe joined webs so as to bring the second lines of adhesive on the outersurface of the second strip against an outer surface of the first stripto join them together. Thus a continuous layer of strips of materialjoined along alternately staggered spaced adhesive lines is provided,and when this layer is drawn out an expanded cellular construction isprovided, as disclosed in applicants above noted prior patent U.S. Pat.No. 3,257,253.

'As with all production equipment, it is desirable that the equipmentfunction to produce a maximum quantity of the product in any given time.One of the problems in the prior art equipment as exemplified by theapparatus disclosed in appli' cant's aforementioned patent is that asingle layer of cellular honeycomb material is produced at the outputend of the equipment. Though production is continuous, the rate ofproduction is limited, and it is found that the subsequent expansion ofthe formed core does not occupy the full time of the operator's handlingthe core after production on the equipment.

Additionally, where it is desired to have different thicknesses ofhoneycomb available, it is necessary to readjust the cutters requiringseparate production runs and'down time between each production run,increasing the cost of production.

SUMMARY OF THE INVENTION It is with the above considerations in mind,that the present improved honeycomb forming method and apparatus hasbeen evolved serving to permit the simultaneous continuous formation ofa plurality of sheets of honeycomb material of selectively variablethickness. 1

ous production of different selected thicknesses of honeycomb.

These and other objects of the invention which will become hereafterapparent are achieved in accordance with the novel method of thisinvention by feeding two or more webs of sheet material of the typewhich it is desired to form into the honeycomb core along a desiredproduction path; and joining the webs of sheet material as they arebeing fed by applying spaced lines of adhesive between the webs alongtheir direction of feed, and bringing the webs into contact to join themalong the spaced adhesive lines, and applying a second set of spacedlines of adhesive arranged between the previously applied adhesive lineson an outer face of the joined webs. Thereafter a group-strip is cutfrom the adhered first and second webs of material transverse to thedirection of web feed, said group-strip equal in length as measuredalong the web to the thickness of two or more layers of core material tobe formed. This group-strip is then cut into strips of a length equal tothe thickness of the desired core layers and simultaneously packedagainst previously cut group-strips so that the final line of adhesiveof the cut group-strips contact the rear face of the previously cutstrips, to join the cut groups of strips. In packing the group-stripstogether, they are simultaneously cut and separated so that dependent onthe number of strips in the group, a corresponding number of sheets orlayers of honeycomb will be formed.

A novel apparatus is provided for performing the above method employingsupports for two or more supply rolls of webs of sheet material, and webguiding rolls for feeding the sheet material adjacent adhesiveapplicators which apply the first series of spaced lines of adhesive toone side of one of the webs which is thereafter brought against the faceof the other web over laminating rolls to adhere said webs. A finalgroup of adhesive lines is applied on the outer face of the joined websspaced between the first row of adhesive lines. Thereafter positioned inthe path of the laminated first and second webs is a sheet cutter in theform of a rotary knife cutting a groupstrip from the web. Sheet feedlines engage the group-strip moving it from the cutter at a linear speedgreater than that of web feed to a packing-cutting zone where areciprocating packer bar with die cutting blades simultaneously cuts thegroup-strip into strips equal in length to the thicknesses of the layersof core material to be formed and packs the cut strips against thepreviously cut strips of a previous group-strip to adhere the stripsinto the desired core layers.

BRIEF DESCRIPTION OF THE DRAWING FIG. 3 is an enlarged perspectivedetail view of the blade supporting portion of the cross-head beam ofthe die-cutter packer.

DESCRIPTION OF PREFERRED EMBODIMENT OF THE INVENTION Referring now moreparticularly to the drawing, like numerals will be employed to designatelike parts in the various figures.

The honeycomb forming apparatus 10 is seen to comprise a web rollsupport stand 15 having bearing blocks 18 and 20 for rotatablysupporting rolls of a first and second web of sheet material 24 and 22respectively. As will be understood by those skilled in the art, avariety of different types of roll stands may be employed for supportingrolls of sheet material to be fed.

- The sheet material which may be used in conjunction with theheredisclosed apparatus for forming desired honeycomb may be kraftpaperboard, aluminurn foil, steel foil, fiberv glass, felted cottonwebbing, asbestos board, or anyone of a wide variety of sheet materials.Applicant has successfully processed webs of sheet material 6 feet inwidth, with a stock thickness of between 0.001 inches and 0.03 inches.

Thefirst web of sheet material 24 (the one to the right in the drawing)is trained under threading roll 25, whence it is guided upwardly toadhesive applicator which applies a first set of spaced lines ofadhesive to one face of the web 24 (the web fac'e to the right in FIG.1). The glue applicator 30 may take a variety of forms, such for exampleas shown in FIG.

4 of applicants prior patent US. Pat. No. 3,257,253, but ispreferably asschematically shown in FIGS. 1 and 2 as comprising a liquid adhesivechamber 31 containing an adhesive 32. The adhesive 32 may be anyone of avariety of adhesives,

suitable for the material being processed. Polyvinyl acetates epoxies,hot melts and the like have been found suitable.

An adhesive pickup roll 33 is arranged to dip into the adhesive 32 as aresult of which the surface of pickup roll 33 will be coated with theadhesive. Pickup roll 33 rotates in contact with adhesive transfer roll34 and coats this transfer roll 34 with adhesive. In order to formdesired strips of adhesive, doctor blade 35 having notches 36 spaced tocorrespond to the desired spacing between the lines of adhesive wipesthe surface of roll 34. Applicator roll 37 is arranged to contact theweb. If desired the doctor blade 35 may be arranged to wipe theapplicator roll. As will be understood the adhesive remaining on theroll after wiping by the doctor blade is applied to the web surfacecontacted by the applicator roll 37. Backing roll 38 serves to insurethe training of the web 24 adjacent the adhesive applicator roll 37 ascan be seen in the drawing;

' Second web 22 (coming from the roll to the left in the drawing) movesunder guide roll 42, and over guide rolls 43 and 44 to laminating roll46. As will be observed from the drawings, at laminating roll '46,second web 22 comes into contact with first web 24 along the surface ofweb 24'to which the spaced lines of adhesive have been applied by theadhesive applicator 30.

From the laminating'roll 46 the combined webs 22-24 are fed to nip rolls50 and 51, between which the joined web 22-24 passes to second glueapplicator which may be substantially identical to first glue applicator30, as above described. The doctor blade on this second glue applicator60, is shown as applied to the applicator roll, and the notches arespaced apart a distance equal to the spacing between the notches 36 onglue applicator 30,'are staggered with respect to the first notcharrangement so that the lines of glue applied by the second glueapplicator lie intermediate the lines of glue applied by the firstapplicator, as described and illustrated in applicants prior patent US.Pat. No. 3,257,253.

Arranged in the path of travel of webs 22-24 as they leave the secondglue applicator 60 are sheet cutting means illustratively shown as inthe form of 'a rotary sheet cutter having cylinder 66'on which ismounted cutter blade 67 arranged to move against anvil 68. Web guides 69and 70 are positioned between second adhesive applicator 60 and therotary sheet cutter 65 to insure proper guiding of the laminated web22-24 to the rotary cutter 65. Web guide 70 may be a solid plate, whileguide 69 is formed preferably by spaced strips 'lying between theadhesive lines.

The strip cut by cutting means 65 is herein referred to as agroup-strip" indicating that the length of the group-strip as measuredalong the web is equal to the thickness of two or more layers of thecore material to be formed.

Downstream of rotary cutter 65, and positioned to receive thegroup-strips of laminated sheeting 22-25 separated from the web by theaction of cutter knife 67 is driven strip sheet feed assembly 75, whichin the illustrated embodiment is schematically shown as comprised byendless groups of feed lines 76 and 77 in the form of loops mounted overpulleys so that the feed lines 76 and 77 sandwich and guide thelaminated web 22-24. As will be understood by those skilled in the art,

. of the strip feeder should be carefully oriented with respect to thecutting roll 66 so that theleading edge of the cut strip is engaged bythe infeed end of the strip feeder immediately upon cutting, and thesurface speed of the strip feeders should be greater than the linearspeed of the sheet cutting knife 67, for a purpose to become hereinaftermore apparent.

' A die cutting and packing. assembly 85 is provided downstream of thesheet feeder to receive the group-strip cut from laminated web 22-24.The die cutter and packing assembly is an improved variation of thestrip cutter and packing apparatus shown in applicant's prior patent US.Pat. No. 3,307,440, and comprises a reciprocably mounted bladesupporting cross-head beam 86. The blade supporting reciprocablecross-head beam 86 is mounted for reciprocation on guide rails 87 and88, and reciprocated by connecting rod I 89 connected to crank 90drivenby motor 91, as schematically illustrated. One or more die cuttingknives 94 is held between spacers 95 in the reciprocating block 86extending into the path of movement of the strip coming from stripfeeder 75, with the number of knives selected depending on the number ofstrips to be cut from the group-strip which has already been cut byrotary cutter 65 In the illustrated embodiment, three cutter blades 94are shown positioned between spacer blocks 95. As will be apparent tothose skilled in the art, the thickness of the spacer blocks, may bevaried selectively to provide for different blade spacing, as a resultof which the strip will be cut into different thicknesses.

Packing chamber is formed by an .upper packing plate 101, and a lowerpacking plate 102, which packing plates 10] and 102 are preferablymounted to permit vibration thereof as by vibrators 103, so as toimplement desired flow of the cut groups of strips there between.

At the outlet end of the packing chamber 100, it is preferred to providetwo or more discharge tables (four of which are here shown) 105, 106,107 and 108, each table aligned with one of the sheets of honeycombproduced by the packing of the strips into the packing chamber 100.

OPERATION In use, the aforedescribed apparatus may be employed inpracticing methods of this invention. It will however be apparent tothose skilled in the art that a wide variety of variation in apparatusmay be utilized to perform the disclosed steps.

According to the method of the invention, two or more webs of sheetmaterial to be fabricated into the core are fed along a flow pathleading to a packing-cutting zone. One of the sheets of material, on'theface thereof facing the other sheet of material is provided with aplurality of spaced lines of adhesive, and the two sheets are laminatedtogether along these spaced lines of adhesive by bringing them intocontact as they move along the webs flow path. Thereafter a second groupof spaced lines of adhesive is applied to the external surface of one ofthe sheets, with the second group of spaced lines of adhesive beingstaggered to lie between the first lines of adhesive. Group-strips ofthe laminated sheet material are cut from the web advancing along thewebs flow path, with the length of the cut group-strip as measured alongits direction of feed totaling the thickness of two or more layers ofhoneycomb to be formed. After cutting of this group-strip, thegroup-strip is fed along the web flow path at a speed greater than thespeed of the web prior to cutting, and advancing to a position where twoor more strips are cut from this group-strip, with the resulting groupof strips simultaneously packed against a previously cut group of stripsso as to cause the second lines of adhesive to join the last cut groupof strips with the previously cut group of strips.

The schematically illustrated apparatus here presented as suitable forpracticing the method of the invention is used by positioning rolls ofwebs of desired sheet material on the roll stand 15. The web from eachroll is trained along the flow path illustrated in FIG. 1, with thefirst web (to the right in the drawing) moving adjacent adhesiveapplicator 30, which as above described, applies a series of spacedlines of adhesive to .the face of web 24 facing web 22.

Web 22 coming from the roll to the left in the drawing meets up with theadhesive stripped face of web 24 at laminating roll 46, where the webs22 and 24 are laminated together, and fed to nip rolls 50, 51. Accordingto the illustrated preferred embodiment of the invention, it is foundthat desired power for movement of the webs can be obtained merely bydriving nip rolls 50, 51, with all of the previously described rollsbeing friction driven. Selected drives may however'be employed shouldsuch be found desirable depending on the weight of the stock beingprocessed, the rate of speed, and any of a variety of mechanical factorsnormally providing criteria for determining whether feeding rolls aredriven or idle. In operating with 6 foot wide sheet stock of a thicknessless than 0.03 inches, a satisfactory rate of speed of 50 feet perminute for the laminated webs 22-24 is found to produce satisfactoryresults.

The laminated web 22-24 is fed through second adhesive applicator 60,which as above described provides a series of spaced lines of adhesive,with the spacing between the lines of adhesive equal to the spacingbetween the first lines of adhesive, but being staggered to lie betweenthem, on an outer face of web 24.

The externally adhesive stripped laminated web 22-'-24 is then fed at 50feet per minute to the cutting station, at which the speed of cuttingroll 66 is regulated depending on the total of the thickness of thehoneycomb layers to be produced simultaneously. Thus if four l is inchthickness of honeycomb are to be produced at the same time, it will benecessary to cut a six inch strip from the advancing web, and a cuttingroll rotating at 100 rpm. with a single cutterblade 67 will cut off such6 inch strips. The radius of the cutting roll 66, and the positioning ofthe intake rolls ofthe strip feeder 75 are such that the leading edge ofthe cut off strip is gripped simultaneously as it is cut. The linearspeed of the group-strip feeders 75 is selected to be greater than theinitial web feed speed, and is selected to be co-ordinated with the rateof reciprocation of the packing die cutting assembly 85, with the lengthof the path of the strip feeder being such as to insure the fact that noadvancing group-strip interfered with the reciprocation of the packer.With a packer head 86 reciprocating at 400 strokes per minute, the stripfeeder 75 should feed the cut strip of a 6 inch length at 200 feet perminute. Lesser or greater speeds may obviously be employed, the onlyconsideration required being that the speed of the strip feeder, and thespeed of reciprocation of the packer be co-ordinated, with the speed ofthe strip feeder being greater than the speed of web feed to the cutter65 so as to provide some short time interval during which there is nomaterial flow to the packer as it is reciprocating.

It will be seen from the foregoing, that knife positioning in the packerdie cutter 86 may be selected to provide simultaneous cutting ofdifferent thicknesses of honeycomb, and continuous production can beobtained of a plurality of like or different thicknesses of honeycomb.

What is claimed is: i

1. Honeycomb forming means comprising sheet feeding means feeding aplurality of webs of sheet material toward a packing-cutting zone;attaching means along the line of feed of the webs of sheet materialsecuring adjacent webs together along spaced lines extending along thedirection of web feed; an applicator applying spaced lines of attachingmeans to an outer surface of the attached webs; cutting means in thepath of travel of the attached webs severing a group-strip from theapplicator comprises an applicator roll contacting said outer attachedwebs equal in length as measured in the direction of web feed to thethickness of a plurality of layers of the honeycomb to be formed; stripadvancing means engaging the group-strip and advancing it toward thepacking-cutting zone at a rate faster than the rate of feed of the websto said cutting means; and packing-cutting means receiving thegroup-strip advanced by said strip advancing means, engaging saidgroupstrip to pack and simultaneously cut said group-strip into aplurality of separate strips each equal in length as measured along thedirection of web feed to the thickness of a layer of the honeycomb to beformed.

2. Honeycomb forming means as in claim 1 in which said attaching meanscomprise an adhesive applicator having: an adhesive chamber; an adhesivepickup roll mounted to rotate with at least a portion thereof dippinginto the adhesive in said chamber; an adhesive transfer roll contactingsaid pickup roll; an applicator roll contacting said pickup roll and theface of one of the webs facing another web as the webs are fed; and adoctor blade above said chamber wiping the adhesive transferred fromsaid pickup roll to only permit the application of spaced lines ofadhesive to the web contacted by said applicator roll.

3. Honeycomb forming means as in claim 2 in which said attaching meansincludes a laminating roll downstream of said attaching means along thepath of travel of the webs over which the webs are trained afterapplication of adhesive to the face of one of the webs to bring theadhesive stripped surface of one web against another web, saidlaminating roll being above said applicator, whereby any excess adhesivesqueezed out by the passage of the webs over said laminating roll willdrain down along the surfaces of the web.

4. Honeycomb forming means as in claim 1 in which said applicatorcomprises an adhesive applicator applying spaced lines of adhesive tosaid outer surface of the attached webs.

5. Honeycomb forming means as in claim 4 in which said web surface; anda doctor blade having a roll wiping edge with a series of spacednotches, the unnotched edge portions of the blade contacting the surfaceof said applicator roll to remove adhesive from said roll except at thenotched portions of the blade.

6. Honeycomb forming means as in claim 1 in which said cutting meanscomprise a rotary cutter comprising a roll rotating about an axistransverse to the direction of web feed; and a cutter blade on said rollintercepting the web to cut a groupstrip from said web on every rotationof said roll.

7. Honeycomb forming means as in claim 1 in which said strip advancingmeans comprise a plurality of endless feed lines trained over opposedpairs of pulleys, with the groupstrip sandwiched between the feed lines,said feed lines spaced to lie between the spaced lines of attachingmeans applied to the outer surface of the group-strip.

8. Honeycomb forming means as in claim 1 in which said packing-cuttingmeans comprise: a reciprocably mounted cross-head beam moving totraverse the path of feed of the group-strips from said stn'p advancingmeans; and a plurality of die cutting blades in said head spaced apart adistance equal to the thickness of the desired layers of honeycomb to beformed.

9. Honeycomb forming means as in claim 8 in which a packing chamber isarranged in the path of said reciprocating cross-head beam into whichthe cut group strip is forced by the reciprocating cross-head, saidpacking chamber comprising an upper and lower wall spaced apart adistance equal to 12. In a honeycomb forming machine in which webs ofsheet stock attached along spaced lines are fed to a packingcuttingzone, a packer-cutter in the packing-cutting zone comprising: areciprocating cross-beam reciprocating across the path of web feed; anda plurality of die cutting knives in said cross-head extending from theleading face thereof, said knives spaced apart with a distancetherebetween equal to the thickness of a layer of honeycomb to beformed, the number of knives being such as to cut at least two strips toform at least two layers of honeycomb simultaneously.

13. In a honeycomb forming machine as in claim 12, a packing chamber inthe path of reciprocation of said crossbeam, said chamber comprising: anupper and lower wall spaced apart a distance equal to the thickness ofthe plurality of layers of honeycomb being formed.

14. A method of forming honeycomb comprising the steps of feeding aplurality of webs of sheet material toward a packing-cutting zone;attaching said fed webs toeach other along spaced lines extendingalongthe direction of web feed; applying attaching means to an outer surfaceof the attached webs along spaced lines lying between the lines ofattachment of the attached webs; and simultaneously cutting a pluralityof strips of the attached webs, each strip equal in length as measuredalongthe web to the thickness of a layer of honeycomb to be formed, andwhile cutting the plurality packing the cut strips against a pluralityof previously cut strips. I

15. A method as in claim 14 in which the plurality of cut strips areconfined to resist, the force of packing the sub sequently cut strips.

16. A method of forming honeycomb comprising the steps of:

continuously feeding contacting webs of sheet stock of which thehoneycomb is to be formed toward a packingcutting zone, said w'ebs beingadhered together along spaced first lines parallel to the direction ofweb feed, and one of the outer faces of said contacting webs havingsecond lines of adhesive parallel to and between said first lines;cutting group-strips transversely from said contacting webs as they arefed to the packing-cutting zone, in advance of the packing-cutting zone,each group-strip being equal in length as measured along the web to atleast two of the thicknesses of the layers of honeycomb to be formed;

advancing the cut group-strip after it is cut at a faster rate of speedthan the speed of web feed to the packing-cutting zone;

packing and simultaneously cutting the group-strip at thepacking-cutting zone by forming, and simultaneously cutting thegroup-strip against previously packed and cut group-strips tosimultaneously form two or more layers of honeycomb.

" k n: I

1. Honeycomb forming means comprising sheet feeding means feeding aplurality of webs of sheet material toward a packingcutting zone;attaching means along the line of feed of the webs of sheet materialsecuring adjacent webs together along spaced lines extending along thedirection of web feed; an applicator applying spaced lines of attachingmeans to an outer surface of the attached webs; cutting means in thepath of travel of the attached webs severing a group-strip from theattached webs equal in length as measured in the direction of web feedto the thickness of a plurality of layers of the honeycomb to be formed;strip advancing means engaging the group-strip and advancing it towardthe packing-cutting zone at a rate faster than the rate of feed of thewebs to said cutting means; and packing-cutting means receiving thegroup-strip advanced by said strip advancing means, engaging saidgroup-strip to pack and simultaneously cut said group-strip into aplurality of separate strips each equal in length aS measured along thedirection of web feed to the thickness of a layer of the honeycomb to beformed.
 2. Honeycomb forming means as in claim 1 in which said attachingmeans comprise an adhesive applicator having: an adhesive chamber; anadhesive pickup roll mounted to rotate with at least a portion thereofdipping into the adhesive in said chamber; an adhesive transfer rollcontacting said pickup roll; an applicator roll contacting said pickuproll and the face of one of the webs facing another web as the webs arefed; and a doctor blade above said chamber wiping the adhesivetransferred from said pickup roll to only permit the application ofspaced lines of adhesive to the web contacted by said applicator roll.3. Honeycomb forming means as in claim 2 in which said attaching meansincludes a laminating roll downstream of said attaching means along thepath of travel of the webs over which the webs are trained afterapplication of adhesive to the face of one of the webs to bring theadhesive stripped surface of one web against another web, saidlaminating roll being above said applicator, whereby any excess adhesivesqueezed out by the passage of the webs over said laminating roll willdrain down along the surfaces of the web.
 4. Honeycomb forming means asin claim 1 in which said applicator comprises an adhesive applicatorapplying spaced lines of adhesive to said outer surface of the attachedwebs.
 5. Honeycomb forming means as in claim 4 in which said applicatorcomprises an applicator roll contacting said outer web surface; and adoctor blade having a roll wiping edge with a series of spaced notches,the unnotched edge portions of the blade contacting the surface of saidapplicator roll to remove adhesive from said roll except at the notchedportions of the blade.
 6. Honeycomb forming means as in claim 1 in whichsaid cutting means comprise a rotary cutter comprising a roll rotatingabout an axis transverse to the direction of web feed; and a cutterblade on said roll intercepting the web to cut a group-strip from saidweb on every rotation of said roll.
 7. Honeycomb forming means as inclaim 1 in which said strip advancing means comprise a plurality ofendless feed lines trained over opposed pairs of pulleys, with thegroup-strip sandwiched between the feed lines, said feed lines spaced tolie between the spaced lines of attaching means applied to the outersurface of the group-strip.
 8. Honeycomb forming means as in claim 1 inwhich said packing-cutting means comprise: a reciprocably mountedcross-head beam moving to traverse the path of feed of the group-stripsfrom said strip advancing means; and a plurality of die cutting bladesin said head spaced apart a distance equal to the thickness of thedesired layers of honeycomb to be formed.
 9. Honeycomb forming means asin claim 8 in which a packing chamber is arranged in the path of saidreciprocating cross-head beam into which the cut group strip is forcedby the reciprocating cross-head, said packing chamber comprising anupper and lower wall spaced apart a distance equal to the thickness ofthe plurality of layers of honeycomb formed from the group-strip. 10.Honeycomb forming means as in claim 9 having vibrating means coupled toat least one of said packing chamber walls.
 11. Honeycomb forming meansas in claim 9 having a plurality of discharge tables at the outlet endof said packing chamber, one table of said plurality aligned to supportone of the layers of honeycomb being simultaneously formed in saidchamber.
 12. In a honeycomb forming machine in which webs of sheet stockattached along spaced lines are fed to a packing-cutting zone, apacker-cutter in the packing-cutting zone comprising: a reciprocatingcross-beam reciprocating across the path of web feed; and a plurality ofdie cutting knives in said cross-head extending from the leading facethereof, said knives spaced apart with a distance therebetween equal tothe thickness of a layer of honeycomb to be formed, the nUmber of knivesbeing such as to cut at least two strips to form at least two layers ofhoneycomb simultaneously.
 13. In a honeycomb forming machine as in claim12, a packing chamber in the path of reciprocation of said cross-beam,said chamber comprising: an upper and lower wall spaced apart a distanceequal to the thickness of the plurality of layers of honeycomb beingformed.
 14. A method of forming honeycomb comprising the steps offeeding a plurality of webs of sheet material toward a packing-cuttingzone; attaching said fed webs to each other along spaced lines extendingalong the direction of web feed; applying attaching means to an outersurface of the attached webs along spaced lines lying between the linesof attachment of the attached webs; and simultaneously cutting aplurality of strips of the attached webs, each strip equal in length asmeasured along the web to the thickness of a layer of honeycomb to beformed, and while cutting the plurality packing the cut strips against aplurality of previously cut strips.
 15. A method as in claim 14 in whichthe plurality of cut strips are confined to resist the force of packingthe subsequently cut strips.
 16. A method of forming honeycombcomprising the steps of: continuously feeding contacting webs of sheetstock of which the honeycomb is to be formed toward a packing-cuttingzone, said webs being adhered together along spaced first lines parallelto the direction of web feed, and one of the outer faces of saidcontacting webs having second lines of adhesive parallel to and betweensaid first lines; cutting group-strips transversely from said contactingwebs as they are fed to the packing-cutting zone, in advance of thepacking-cutting zone, each group-strip being equal in length as measuredalong the web to at least two of the thicknesses of the layers ofhoneycomb to be formed; advancing the cut group-strip after it is cut ata faster rate of speed than the speed of web feed to the packing-cuttingzone; packing and simultaneously cutting the group-strip at thepacking-cutting zone by forming and simultaneously cutting thegroup-strip against previously packed and cut group-strips tosimultaneously form two or more layers of honeycomb.